Pretty standard. What is for you a non-diamond or a blank?
Do you think he has many hands which would Bet for value there?

Best Regards.

Something like Q
or 3
. I don't think he'll bet many hands for value tbh, why would he bet with an 8... So probably check/call is best on the river (ofcourse depending on his size)

Correcto, only reasonable hand might be 78, though only problem that the guy may still bet for thin value with something like TT/JJ, you have to watch out for those opponents. Especially if they are nitty.